1. Field of the Invention
The present disclosure relates to an image pickup technology using a solid-state image pickup element.
2. Description of the Related Art
As discussed in, for example, Japanese Unexamined Patent Application Publication No. 2007-96825, a related compound-eye image pickup device using solid-state image pickup elements (photodetectors) uses a structure in which a plurality of lenses and a set of photodetectors (disposed for the respective lenses) are disposed so as to be separated from each other by a focal length of each lens, and, in which, from a plurality of images picked up by the set of photodetectors, parallax information of each image is used to reproduce one image.
However, the related compound-eye image pickup device having such a structure has the following problems:
(1) Since it is necessary to dispose the photodetectors so as to be separated from the lenses by the focal length, the image pickup device becomes thick. Although it is possible to shorten the focal length by using lenses having high refractive indices, aberrations, such as chromatic aberration, are inevitably increased, thereby reducing image quality of a picked up image;
(2) Since, in an ordinary image pickup device, a focusing operation must be performed in accordance with the distance to a pickup object when an image pickup operation is performed, it is difficult to perform continuous shooting operations by changing a focus. For example, if a lens system includes one lens, the lens must be replaced in accordance with the focal length. In addition, if a lens system includes a plurality of lenses, focusing must be performed by changing the distance between the lenses. Such problems also similarly occur in the compound-eye image pickup device; and
(3) A step for aligning the lens system and the photodetectors when manufacturing the image pickup device is required. This step causes costs of a product to be increased.
Therefore, there is a demand for overcoming these problems.